Project description:Differences in the transcriptional profile of the menigococcal strains MC58 and α710 were compared upon growth in PPM+ and on exposure to human saliva, whole blood and cerebrospinal fluid
Project description:The Gram-negative bacterium Neisseria meningitidis causes meningitis in humans and has been demonstrated to manipulate or alter host signalling pathways during infection of the central nervous system. In this study, the phosphoproteome of an in vitro model of the blood-cerebrospinal fluid barrier was investigated during infection with the Neisseria meningitidis serogroup B (NmB) strain MC58 in presence and absence of the bacterial capsule. We show that the capsule deficient mutant has a higher impact on the phosphoproteome of the infected cells and identify potentially regulated pathways and cellular processes during infection.
Project description:Neisseria meningitidis is an obligate commensal colonising the human nasopharynx and occasionally invades the bloodstream causing life-threatening meningitis and septicaemia. The gene NMB0419 on the genome of N. meningitidis MC58 encodes a putative Sel1-like repeat (SLR) containing protein, which has been implicated in mediating meningococcal invasion of epithelial cells. We prepared RNA samples from N. meningitidis MC58 (WT) and its isogenic mutant of NMB0419 grown to log phase in in-vitro culture. The RNA samples were subjected to RNA sequencing. The resulting transcriptomes were compared to determine the genes that differentially expressed in NMB0419 mutant.
Project description:The zur regulon in Neisseria meningitidis was elucidated in the strain MC58 using a zur knockout strain and conditions which activate Zur ( zinc supplementation in the medium)
Project description:Microarray comparative genome hybridization (mCGH) data was collected from one Neisseria cinerea, two Neisseria lactamica, two Neisseria gonorrhoeae, and 48 Neisseria meningitidis isolates. For N. meningitidis, these isolates are from diverse clonal complexes, invasive and carriage strains, and all major serogroups. The microarray platform represented N. meningitidis strains MC58, Z2491, and FAM18 and N. gonorrhoeae FA1090.
Project description:The human-specific, Gram-negative bacterium Neisseria meningitidis (Nm) is a leading cause of bacterial meningitis world-wide. It has been described that Nm can enter the central nervous system via the blood-cerebrospinal fluid barrier (BCSFB), which is constituted by the epithelial cells of the choroid plexus. Using a recently established in vitro model of the human BCSFB based on human malignant choroid plexus papilloma (HIBCPP) cells we investigated the cellular response of HIBCPP cells challenged with the meningitis-causing Nm strain MC58. In comparison we analysed the answer to the closely related unencapsulated carrier isolate Nm M-NM-114. Transcriptome analysis revealed a stronger transcriptional response after infection with strain MC58, in particular with its capsule deficient mutant MC58siaD-, which correlated with bacterial invasion levels. Expression evaluation and Gene Set Enrichment Analysis pointed to a NF-M-NM-:B-mediated pro-inflammatory immune response involving up-regulation of the transcription factor IM-NM-:BM-NM-6. Consistent with this, infected cells secreted significant levels of pro-inflammatory chemokines and cytokines, among others, IL8, CXCL1-3 and the IM-NM-:BM-NM-6 target gene product IL6. Expression profile of pattern recognition receptors in HIBCPP cells and the response to specific agonists indicates that TLR2 rather than TLR4 is involved in the cellular reaction following Nm infection. Human malignant choroid plexus papilloma (HIBCPP) cells were infected from the basolateral side with the meningitis-causing Neisseria meningitidis disease isolate MC58, its non-capsulated mutant MC58siaD- and the Neisseria meningitidis carrier isolate M-NM-114 for 4 h.The transcriptional response of HIBCPP cells to the different Neisseria meningitidis strains was evaluated by microarray analysis. Untreated HIBCPP cells served as control. Three replicates of each condition were analysed.
Project description:Wild type Neisseria gonorrhoea strain FA1090 and N. meningitidis strain MC58 were grown on normal GC plate at either 35 degree celsius (for control samples) or 40 degree celsius (for test samples)
Project description:We identified twin small non-coding RNAs regulating tricarboxylic acid (TCA) cycle activity in Neisseria meningitidis. Expression of TCA cycle enzymes was elevated in sRNA deletion mutants. Direct interaction between sRNAs and the ribosomal entry sites on target mRNAs was demonstrated. Expression of the sRNAs was down-regulated in cells grown in poor medium with glucose as the sole carbon source but not without lrp, indicating that sRNA expression is controlled by the stringent response. N. meningitidis, over-expressing the sRNAs replicated in blood, but not in human cerebrospinal fluid. In addition, Lrp synthesis was inhibited by direct interaction between the sRNA and the 5’ UTR of lrp. sRNAs control adaptation of N. meningitidis to variation in nutrient supply in different niches of its host.
Project description:The zur regulon in Neisseria meningitidis was elucidated in the strain MC58 using a zur knockout strain and conditions which activate Zur ( zinc supplementation in the medium) Common reference design, zur knock out strain was used as the common reference and the samples wild type strain grown in RPMI and in RPMI with Zinc supplementation were compared to the common reference.
